JP7472308B2 - Clamping insert for clamping jaws of a clamping chuck, set of clamping inserts and method for clamping a toothed component - Patents.com - Google Patents

Description

The present invention relates to a clamping insert having a plurality of clamping teeth for clamping jaws of a clamping chuck, formed according to the preamble of claim 1. Furthermore, the present invention relates to a method for clamping a toothed component with its teeth, i.e. with the external or internal teeth.

Clamping inserts for clamping chucks are known, for example, from EP 1 683 596 B1. The known clamping insert has a body which is provided for connecting the clamping jaws of a clamping chuck. The body is provided with one or more clamping teeth and has a contact surface as a stop for the workpiece to be clamped. The clamping teeth, in the case of EP 1 683 596 B1, have to be pressed into the workpiece while displacing material.

DE 31 22 876 A1 describes gripper jaws for a jaw chuck configured as a powered or manual clamping chuck on a machine tool. The gripper jaws have an adjustment jaw in each case connected to a clamping tooth in the radial adjustment direction of the jaw chuck for holding the workpiece. The clamping tooth is then arranged on a separate clamping insert which is inserted non-rotatably in the axial guide of the adjustment jaw. The clamping insert can be held by a screw such that there is radial play of the clamping insert. Rotation of the clamping insert is prevented by the side wall of the axial guide which guides the clamping insert.

A clamping claw insert that is releasably fixed from the clamping jaws of a machine tool is also described in DE 38 10 854 A1. The clamping claw insert in this case consists of a roller body that can be pushed into a receiving opening with its longitudinal axis parallel to the axis of rotation of the workpiece to be clamped and is supported for rotation therein. At the same time, the clamping claw insert is supported in a form-locking manner in its axial and lateral directions. The clamping claw insert is fixed by means of a fastening screw that leaves the clamping claw insert with some movement play. The eccentricity between the clamping claw insert and the fastening screw, together with a suitable fit, must result in the clamping claw insert always being automatically adjusted by the clamping teeth in the direction towards the surface of the workpiece when the clamping chuck is closed.

DE 10 2008 064 525 A1 discloses a method for connecting clamping jaws using a clamping device, in which the clamping device has a number of clamping tool receptacles in which a clamping tool is guided in each case by means of a region of the clamping tool receptacle that extends at an angle to the clamping direction. The clamping tool is composed of a clamping jaw carrier and a clamping jaw, which engages in an undercut of the clamping jaw carrier and is further fixed by a form-locking fastener.

A clamping chuck adapted for clamping externally toothed components is known from DE 670 330 A. The known clamping chuck is a three-jaw chuck for clamping a gear against the flanks of the toothing. The three clamping jaws are provided with flat surfaces which form the sides of an imaginary equilateral triangle. In the case of DE 670 330 A, three rows of racks are used which mesh with the gear to be clamped. The racks are supported in the jaws of the clamping chuck by means of rollers, so that they can be aligned in accordance with the desired triangle.

A further clamping chuck for gears is known from DE 1 104 855 B. This clamping chuck has separate teeth which mesh between the teeth of the gear to be clamped. The number of teeth of the clamping chuck therefore corresponds to the number of teeth of the gear.

A clamping chuck with a single toothed portion that meshes with the teeth of the gears being clamped is also described in U.S. Pat. No. 2,678,824 A. In this case, the single toothed portion of the clamping chuck meshes with the second tooth space of each of the gears being clamped.

For clamping toothed workpieces, a clamping device is also provided, as described in U.S. Pat. No. 2,543,117 A. In that case, each replaceable toothed clamp insert is held by a single screw which passes through an oblong hole in the clamp insert and is thereby adjustable.

A clamping chuck formed as a four-jaw chuck for clamping gears is disclosed in the specifications of Chinese Utility Model No. 201389762Y and Chinese Patent No. 101508040A. It is then adjustable by means of an adjustment bolt. Yet another device for centering and fixing gears is disclosed in Russian Patent No. 2069124A.

Various known devices use devices with rollers for tightening the gears, which rollers mesh between the teeth of the gears to be tightened. In this connection, for example, the specifications of East German Patent No. 19486 A1, German Patent No. 3443487 C2, German Patent No. 1808894 A and German Utility Model No. 7622766 U are indicated.

Furthermore, devices with parts that can be rotated relative to one another for tightening externally toothed gears are known. In this connection, mention may be made, for example, of the specifications U.S. Pat. No. 2,445,184 A and EP 1 493 518 A1.

A device for clamping externally toothed workpieces, designed in particular for use in measuring or testing machines, is described in EP 2 700 461 B1. In this case, the mutually intermeshing teeth of the various parts are designed in such a way that they can occupy a neutral angular position in which the tooth flanks of the various teeth do not come into contact with each other.

The object of the present invention is to configure the fastening of externally or internally toothed components with their external or internal teeth in a particularly rational and process-reliable manner, even under mass production conditions.

The object is solved according to the invention by a clamping insert having the features of claim 1. Likewise, the object is solved by a method for clamping an externally toothed component according to claim 13. The embodiments and advantages of the invention described below in relation to the clamping method also apply to the device, i.e. the clamping insert, and vice versa.

The invention is based on the consideration that various problems must be overcome during the machining of heat-treated mass-produced externally or internally toothed components. On the one hand, it is conceivable that the heat treatment will cause distortions, i.e. that the components are no longer round. On the other hand, the teeth of the components may have undercuts in the tooth flanks. In particular in a radial plan view of the tooth cutting part of the workpiece, the teeth may have an arrow shape. For further machining after the heat treatment, a chamfer is performed on the component, which ideally maintains the pitch diameter of the tooth cutting part without damaging the tooth flanks. Even if a toothed soft part, i.e. a workpiece that has not yet been hardened, is clamped with its tooth cutting part either from the inside or from the outside, problems related to the non-ideal, non-centric shape of the tip circle of the workpiece during clamping are also conceivable.

Based on these considerations, a clamping insert for the clamping jaws of a clamping chuck has been proposed, which clamping insert has a holding segment of multi-piece construction, which is fixed to the clamping jaws, in which a single clamping tooth is held. The clamping tooth as a whole presents a toothed engagement profile, which is curved corresponding to the dimensions of the toothed component to be clamped. In the case of an externally toothed component, the curvature of the engagement profile is concave, whereas for an internally toothed component, which is clamped from the inside, it is convex. This means that in both cases, in particular the toothing of the component, i.e. the tip of the clamping tooth which engages with a workpiece having a circular cross-sectional shape, is concentric with the workpiece.

Most of the clamping teeth, in particular all of the clamping teeth arranged on the same holding segment, are accommodated in the holding segment with circumferential play relative to the clamping chuck. Insofar as a single clamping tooth is arranged on a holding segment with play, the play of at least one of the corresponding teeth is given in the circumferential direction of the clamping chuck and thus also to the component to be clamped. In contrast, the axial play of the clamping chuck is present at most only to a minor extent.

In general, a number of clamping inserts, i.e. a set of clamping inserts, are provided for use in the case of a clamping chuck of essentially known construction. In that case, all the clamping inserts of the set are not necessarily formed identically. Rather, in an advantageous embodiment, a first and a second subset of the set can be distinguished. In that case, the first subset only includes clamping teeth with play, whereas the second subset has only one clamping tooth held without play per clamping insert. If the second subset consists of three clamping inserts, there are correspondingly only three clamping teeth fixed without play that are provided for engaging with the external toothing of the component to be clamped.

Of the total of six clamp inserts arranged around the workpiece to be clamped and assembled alternately into the first and second subsets, not all clamp inserts need to be formed in accordance with claim 1.

In all cases, the clamping inserts incorporated in the first subset are clamping inserts having the features of claim 1. The various clamping inserts are in particular mounted in the clamping jaws of the clamping chuck in such a way that three clamping teeth, fixed without play, are distributed evenly around the circumference of the component, i.e. at intervals of 120°. All remaining clamping teeth are automatically aligned when the component is clamped. Furthermore, the first subset of clamping inserts contains only three clamping inserts in a typical embodiment. The set is thereby suitable for use in a clamping chuck with six clamping jaws.

There are various implementation possibilities for the clamping inserts of the second subset: According to a first possible variant, each clamping insert of the second subset comprises three clamping teeth, the central clamping tooth being held without play, while the remaining two-sided, i.e. lateral, clamping teeth of the same clamping insert are guided with circumferential play. Alternatively, each clamping insert of the second subset comprises only a single clamping tooth. This clamping insert can be fixed to the holding segment without play and against rotation, for example by means of a two-winged form-connecting contour. In that case, the anti-rotation device is applied to the central axis of the two-winged clamping tooth, which in the rest of its part has a cylindrical basic form.

The two-winged clamping tooth is also suitable for being guided in the holding segment with circumferential play. In this case, each wing of the clamping tooth is accommodated in a recess of the holding member that is wider than the wing, i.e. extends in the circumferential direction of the clamping chuck, and both the wing and its associated recess have a curvature that corresponds to a pitch circle that is provided across all the wings of the clamping tooth. In this way, in addition to the desired displacement possibility of the clamping tooth, a rotationally fixed stop is also provided.

In general, the gentle clamping of the externally and internally toothed components with their teeth is possible by means of several clamping inserts, each of which is concavely curved corresponding to the dimensions of the externally toothed component or, in the case of the internally toothed component, convexly curved and has a meshing contour formed by a single clamping tooth, being engaged with the teeth of the components to be clamped, so that only a total of three clamping teeth are fixed without play in the clamping insert, while all the remaining clamping teeth are guided in the clamping insert with play, i.e. with play in the circumferential direction of the clamping chuck.

The concave or convex curvature of the meshing profile of each clamping insert can be adapted particularly well to the shape of the component to be clamped, in particular the gear, without the need for the use of dedicated rollers, as has been explained many times in the above-mentioned prior art. Furthermore, by adapting the shape of the meshing profile to the profile of the external or internal toothing of the component to be clamped, a stop is achieved in the clamping chuck that is particularly stable and at the same time protects the material of the component.

The multi-piece retaining segment, in which the clamping teeth are retained without play or with a given play, comprises three mutually fixedly joined segments, which are stacked according to a possible embodiment, namely a lower segment provided for resting on the body of the clamping jaw, an intermediate segment resting on the lower segment and an upper segment covering the intermediate segment, with openings formed to accommodate only one clamping tooth in each case in the intermediate segment sandwiched between the other two segments. Thus, each of the two outer segments, i.e. the lower segment and the upper segment, is used as an axial stop for the clamping teeth, the axial direction referring to the central axis of the clamping chuck and the component to be clamped. Also, in an alternative embodiment, there may be a retaining segment configuration consisting of only two pieces or even a one-piece configuration of the retaining segment guiding the clamping teeth.

A single clamping tooth can have a triangular or trapezoidal shape, i.e. the basic form of a wedge. With a wedge-shaped tooth, which in at least some cases is not arranged fixedly on the clamping insert, the tooth can be, so to speak, raised during tightening and retracted in the direction of the wedge towards the stop. In that case, the wedge described by the clamping tooth is directed towards the stop. It has been shown to be advantageous with regard to retraction if the flanks of the clamping tooth are asymmetrically shaped, in particular stepped, so that on each flank of the clamping tooth there are, for example, two stepped sections, which is equivalent to the presence of three surfaces on each flank, spaced apart from one another.

The division of the tooth flank into individual partial surfaces separated from one another by a step is more pronounced on the left tooth flank than on the right tooth flank in the case of an asymmetric tooth shape. In this case, the individual partial surfaces into which the left tooth flank is incorporated can have the same shape as one of the partial surfaces of the right tooth flank, i.e. can be given a partially symmetrical tooth shape. In particular, the flanks connecting to the tooth tips of the clamping teeth can be of the same length. This flank can be provided inclined to describe a plane that meets in front of one of the front faces of the clamping teeth, which is equivalent to one of the front faces taking up a smaller area than the other front face. In other words, the intersection line between both planes lying on the flanks intersects the plane in which the front face of the clamping tooth lies, respectively, at an acute angle. This allows a good adaptation to toothed workpieces of particularly complex shape. In that case, the clamping teeth have an overlapping asymmetry: on the one hand, the two flanks of the clamping teeth are formed unevenly; on the other hand, the mutually parallel front faces of the clamping teeth are differentiated from one another. In particular, the asymmetry of the flanks is an effective measure for the precise insertion of the clamping teeth into the clamping insert.

In particular, in the case of a partially symmetrical tooth profile, i.e. adjacent to the tooth tip, the intermediate flank and the outer flank adjacent to the tooth base together extend more than half the tooth depth measured in the radial direction of the clamping chuck. In this case, the ratio of the height of the outer flank to the height of the intermediate flank is a minimum of 7:10 to a maximum of 13:10 for the first tooth flank and a minimum of 17:10 to a maximum of 23:10 for the second tooth flank.

The tooth root of the clamping tooth, i.e. the tooth back surface, which is opposite the tooth tip and supports inside the clamping insert, in an advantageous embodiment describes a circular arc that is concentric with the entire clamping chuck. This is advantageous for correcting the position of the clamping tooth in the circumferential direction of the clamping chuck. When clamping an externally toothed component, the tooth back surface is convexly curved. When the clamping insert is provided for clamping a component with its internal tooth cutting portion, the tooth back surface is concavely curved.

Independent of the cross-sectional shape of the clamping teeth, each clamping insert may have an odd number of clamping teeth, in particular three clamping teeth. If one of the clamping teeth of the clamping insert is fixed, i.e. fixed without play in the holding segment, it is an intermediate clamping tooth. Independent of the number of clamping teeth per clamping insert, if this number is at least two, the spacing measured in the circumferential direction between the clamping teeth is twice the spacing between the teeth of the component to be clamped. Optionally, the components of the holding segment, which are fixedly fastened by the clamping jaws, are adjustably connected to the respective clamping jaws of the clamping chuck. Theoretically, an externally toothed component can already be clamped by three clamping teeth, each fixedly connected to one clamping jaw. The remaining clamping teeth, guided with play, are used for a more uniform application of force to the component to be clamped and thus for the protection of its teeth. By arranging the clamping teeth of the holding segments spaced apart from one another so that they only engage with the second gaps of the outer teeth of the components to be clamped, a sufficient width of space can be used for the stop with the play of the clamping teeth.

The overall mating profile of the clamp insert may provide a number of teeth that, taken as a whole, matches less than half the number of external teeth on the components being clamped. For example, the total number of teeth on the set of clamp inserts may match a minimum of one-quarter to a maximum of one-half the number of teeth on the external teeth of the workpiece being clamped.

Overall, the component clamped by the clamping insert is gripped at multiple circumferential portions, which for example total more than 210°. The clamping teeth that mesh in the component are divided into, for example, six clamping inserts, so that each of the so-called circumferential portions extends over at least 35°. Commercially available clamping chucks can be equipped at reasonable cost with clamping inserts that are provided for gripping the external teeth. The same applies to clamping chucks that clamp the workpiece at the internal circumference, here the internal teeth.

The components to be fastened are, for example, gears for spur gears or the linkage of a synchronizer for a transmission.

Below, several embodiments of the present invention are described in detail with reference to the drawings.

FIG. 1 is a front view of a clamping chuck for clamping an externally toothed component using a set of clamping inserts. FIG. 2 is a side view of a clamp insert secured to a clamp chuck. FIG. 3 is a perspective view of the assembly shown in FIG. 2 . FIG. 1 is a detailed view of a clamping chuck with a clamping insert secured to the clamping jaws and a clamped external toothed component. FIG. 2 is an exploded view of a first clamp insert of the set of clamp inserts. FIG. 13 is an exploded view of a second clamp insert that is part of a set of clamp inserts. FIG. 13 is a cross-sectional view of an asymmetric clamp tooth. FIG. 8 is a simplified diagram of clamping a workpiece using a clamping insert including the clamping teeth shown in FIG. 7 . 8 is a diagram of the positioning of the clamping teeth of FIG. 7 within a clamping insert of a clamping chuck for clamping a toothed workpiece. FIG. 10 is a view similar to FIG. 9 of clamping a toothed workpiece with only a clamping insert having a single clamping tooth. FIG. 11 is a view of the assembly according to FIG. 10 with an auxiliary component of the clamp insert, which partially covers the clamp teeth. FIG. 8 is a plan view of the clamp tooth shown in FIG. 7; FIG. 13 is a schematic cross-sectional view of the clamp tooth shown in FIG. 12 . 8 is a view similar to FIG. 7 of clamping teeth provided for clamping the workpiece to the internal gear. FIG. 8 is a detailed view of an externally toothed workpiece, i.e., a coupling, clamped with the clamp teeth according to FIG. 7.

The following description relates to all embodiments unless otherwise stated. In all figures, mutually corresponding or essentially equivalent parts are provided with the same reference signs.

The clamping chuck, designated as a whole by reference number 1, has six clamping jaws 2 in the exemplary embodiment. A clamping insert 5 is fixed in each of the base jaws 3 of the clamping jaws 2. The clamping jaws 2 are connected to a base module 6 of the clamping chuck 1, which is basically known from commercially available clamping chucks.

Each clamp insert 5 comprises a retaining segment 4 of multi-piece construction, which has the basic form of a ring segment in front view (FIG. 1). The retaining segment 4 is fixed to its associated base jaw 3, i.e. to the body, by means of a screw 7. The screw with which the clamp jaw 2 is connected to the base module 6 is indicated with 11. Also possible is an integral construction of the base jaw 3 and the clamp jaw 2, as well as an integral construction of the retaining segment 4 and the clamp insert 5.

4, each holding segment 4 is composed of three directly stacked segment parts 9, 10, 17: a lower segment 10 in contact with the body 3, a middle segment 9 resting on the lower segment 10, and an upper segment 17 covering the middle segment 9. The screw 7 passes through all three segment parts 9, 10, 17. In contrast, the screw 8, which is smaller than the screw 7, is provided for each clamp insert 5 only to connect the segment parts 9, 10, 17. The screw 8 can be used as a guide pin when assembling the clamp insert 5.

Each clamping insert 5 defines a concavely curved, toothed engagement contour 12, which is provided for direct interaction with the teeth 14 of the component 13 to be clamped. To facilitate the insertion of the component 13 between the clamping inserts 5, the upper segment 17 of each holding segment 4 has three tooth-shaped insertion aids 15. As soon as the component 13, whose teeth are indicated by 16, is clamped, the insertion aids 15 have no further function.

For engaging the teeth 14, there are rather three clamping teeth 18 per clamping insert 5, which, in relation to the front view according to FIG. 1, are present behind the insertion aid 15. The clamping teeth 18 are inserted into recesses 19 in the intermediate segment 9. In the region of the recesses 19, which each represent one tooth seating surface, the intermediate segment 9 has a thinner wall thickness than the remaining intermediate segment 9. In a corresponding manner, the wall thickness of the upper segment 17 is enlarged in the region in which the insertion aid 15 is present, i.e. in the inner region immediately adjacent to the central axis of the clamping chuck 1, compared to the remaining region further outward of the upper segment 17. This is reflected in the stepped section 20, which is curved in the shape of a circular arc on the inside of the upper segment 17, and in the stepped section 21 of the intermediate segment 9, which is adjacent to the stepped section 20, which is correspondingly curved. The stepped configuration of the upper segment 17 allows a large extension of the insertion aid 15 in the axial direction of the clamping chuck 1 in relation to the thickness of the majority of the upper segment 17.

Two bolts 22 are provided for each holding segment 4 to accurately position the six lower segments 10 in their respective bodies 3. While the lower segments 10 and the upper segments 17 of all holding segments 4 are identically designed, this is not the case for the intermediate segments 9. Rather, the six-piece set of clamping inserts 5 is formed by three first-type clamping inserts 5 (FIG. 5) and three second-type clamping inserts 5 (FIG. 6) that are not visible to the naked eye, or at least not easily distinguishable. The first and second-type clamping inserts 5 are arranged alternately around the circumference of the clamping chuck 1.

Inside the clamp insert 5 of the first type, each recess 19 has the same dimensions, so that the clamp teeth 18 inserted into the recesses 19 are guided with play in the same way. In contrast, in the clamp insert 5 of the second type, the center of the three recesses 19 is narrowed, so that the central clamp teeth 18 are fixed without play in the corresponding clamp insert 5.

Thus, only three of the total of 18 (3 x 6) clamping teeth 18 present according to FIG. 1 are fixedly connected to the body 3 to which they belong, while the remaining 15 clamping teeth 18 are arranged with play on the six clamping inserts 5, in particular in the circumferential direction of the clamping chuck 1. The three clamping teeth 18, each fixed to the body 3, are arranged around the clamping chuck 1 at intervals of 120°.

The individual clamping teeth 18 of each clamping insert 5 mesh with the respective second tooth spaces of the toothings 14 of the component 13. Each of the six clamping inserts 5 extends somewhat less than 60° around the component 13 in order to ensure that the clamping jaws 2 are adjustable and at the same time grip the component 13 over a large part of its circumference. The six peripheral parts of the component 13, i.e. the externally toothed gear, gripped by the clamping inserts 5, add up to a total of more than 210°. Each peripheral segment of the component 13 gripped by the clamping inserts 5 should then be measured between the respective tooth spaces of the toothings 14 which mesh with the teeth 15 with play on both outer sides of the clamping insert 5. The width of such a peripheral segment thereby corresponds to four times the tooth spacing of the external toothings 14.

The stop, which has play in the majority of the clamping teeth 18, allows the meshing contour 12 to be raised when the component 13 is gripped by the clamping chuck 1 on which the set of clamping inserts 5 is mounted. As a result, the component 13 as a whole is clamped with maximum protection of the teeth 14. This also applies if the teeth 16 of the teeth 14 have a shape that deviates from the ideal shape due to manufacturing.

Figure 7 shows an asymmetrically shaped clamping tooth 18 suitable for use in the clamping chuck 1 shown in Figure 1. The tips of the clamping teeth 18 are indicated at 23 and the roots, i.e. the back faces, are indicated at 24. The tooth flanks 25, 29 are indicated as left and right flanks. Each tooth flank 25, 29 is divided into three flanks 26, 27, 28 and three flanks 30, 31, 32, respectively, as becomes clear from Figure 7. Between the flanks 30, 31, 32, stepped portions 35, 36 are discernible. The flanks 26, 27, 28 are separated from one another by stepped portions 33, 34.

The flanks 26, 30 are of the same length and are formed mirror-images of one another. Correspondingly, the stepped portions 33, 35 are arranged at the same height as the toothing 18, the height of which is generally designated H _18. The asymmetry of the toothing 18 is only evident at the portion of the flanks 27, 28, 31, 32. The flank 27 of the left flank 25 extends significantly longer than the opposite flank 31, which represents the middle part of the right flank 29. Conversely, the flank 28 on the left side, adjacent to the tooth root 24, is significantly shorter than the flank 32 on the right side, which also adjoins the tooth root 24. The heights of the flanks 27, 28, 31, 32, measured in the radial direction of the clamping chuck 1, are designated H ₂₇ , H ₂₈ , H ₃₁ , H _32. The sum of H ₂₇ and H ₂₈ corresponds to the sum of H ₃₁ and H ₃₂ . Overall, the asymmetric portion of the tooth 18 formed by the flanks 27 , 28 , 31 , 32 extends more than half the height H ₁₈ of the tooth 18 .

The arrangement of the clamping teeth 18 in the holding segment 4 according to FIG. 7 is shown in a simplified manner in FIG. 8. SpU shows the play of the clamping teeth 18 in the circumferential direction of the workpiece 13 and the clamping chuck 1. Also, corresponding to the arrangement according to FIG. 4, according to FIG. 8 only the clamping teeth 18 mesh with each second tooth groove of the externally toothed workpiece 13.

As is clear from FIG. 9, each clamp tooth 18 is clearly larger than a respective single tooth 16 of the component 13. The cover of the clamp tooth 18, which axially fixes the clamp tooth 18, is not shown in FIG. 9.

A set of clamping chucks 1 includes three clamping inserts 5 of the same kind, each having a triplet arrangement on the clamping teeth 18 with play. Furthermore, the same clamping chuck 1 includes three clamping inserts 5, each also having three clamping teeth 18, as specifically shown in FIG. 7, except that in this case the two outer clamping teeth 18 each have play. In total, the clamping chuck 1 thus includes 15 clamping teeth 18 with play.

In FIG. 10, the clamping insert 5 is shown only with a single clamping tooth 18, which in its cross-sectional shape is clearly different from the wedge-shaped clamping tooth 18 shown in FIG. 7. The clamping tooth 18 according to FIG. 10 has a symmetrical, roller-shaped basic form, in which two wings 37 are discernible on both sides of the clamping tooth 18, i.e., towards the tooth tip 23, each turned by 90°, and which together form an anti-rotation contour 38. The tooth 18 is thus accommodated in the clamping insert 5 in an anti-rotational manner. This applies both to the two-winged clamping tooth 18, which is guided with circumferential play in the clamping insert 5, and to the identically shaped clamping tooth 18, which is fixed without play in the clamping insert 5.

To axially fix the clamping teeth 18 according to FIG. 10, an upper segment 17 is provided, which can be seen in FIG. 11, as compared to the arrangement according to FIG. 4. Three teeth 18 fixed without play, of the shape shown in FIGS. 10 and 11, are distributed around the clamping chuck 1 at intervals of 120°. In the rest of the part, only clamping teeth 18 with play are distributed around the component 13.

The wedge-shaped, asymmetrical stepped clamping tooth 18, as shown in FIG. 7, as well as the substantially roller-shaped clamping tooth 18, as shown in FIG. 10, are predefined to be raised on the tooth cutting portion 14 of the component 13 when there is circumferential play in the clamping chuck 1. This is true within limits that must not be exceeded during mass production, even if the component 13 has a pitch error or is not round, i.e. has a shape that deviates from the ideal circular shape.

The three-dimensional shape of the clamping tooth 18, which is guided with circumferential play in the clamping insert 5, can be seen in particular from Figures 12 and 13. It can be clearly seen that the first front surface of the clamping tooth 18, labeled 39, is smaller than the opposite front surface, labeled 40. As a result, imaginary planes tangent to the flanks 26, 30 adjacent to the tooth tip 23 intersect in front of the front surface 39, as shown by the dashed line in Figure 13. The tooth thickness of the clamping tooth 18, measured between the front surfaces 39 and 40, is labeled SZ.

As regards the tooth back surface 24 that transmits the clamping force, the tooth back surface 24 has an arcuate curved shape that is concentric with the central axis of the entire clamping chuck 1. As a result, the clamping tooth portion 18 is pre-determined to have at least a slight displacement in the circumferential direction of the clamping chuck 1. The transition between the tooth base portion 24 and the side portions 28, 32 is formed as a chamfered portion 41, as can be seen in FIG. 12.

15 shows the geometrical features of the component 13, i.e. the coupling of a transmission synchronizer, which is clamped with the clamping toothing 18 according to FIG. 7. The arrow shape of the toothing 16 of the component 13 is clearly visible. The tooth flanks of the toothing 16 are marked 42. The inclination of the tooth flanks 42 is not only given in the sense that the tooth flanks of the toothing 16 extend from the central axis of the component 13 outwardly in a roof-shaped overlap, as is customary, but also in the plan view, i.e. as shown in FIG. 15, from a line of sight perpendicular to the central axis of the component 13, the planes located on the tooth flanks 42 of adjacent toothings 16 extend in an overlapping manner in the axial direction of the component 13. Correspondingly, as shown by the dashed lines in FIG. 15, at the transition between the tooth root and the tooth flank 42, an acute angle is interposed between the straight lines tangent to the tooth flanks 42 of adjacent toothings 16, respectively. In FIG. 15, the position of these two straight lines coincides with the position of the two internal dashed lines. The two outer dashed lines, which also bracket an acute angle, represent the transition between the tooth surface 42 and the tip of the tooth 16, and also clarify the arrow shape of the tooth 16. The side surfaces 26, 30 contact the tooth 16 when the workpiece 13 is clamped.

Figure 14 shows a cross-sectional shape of the clamping tooth 18, modified compared to the shape shown in Figure 7, in which the clamping of an internally toothed component 13 is intended. The tooth back surface 24 can then be supported on the outer peripheral surface provided by the clamping insert 5, which, as can be seen in Figure 14, has a concave shape and a corresponding radius of curvature. In this case too, the play of the clamping tooth 18 is present in the circumferential direction of the clamping chuck 1.

1 Clamping chuck 2 Clamping jaws 3 Base jaws 4 Retaining segment 5 Clamping insert 6 Base module 7 Screw 8 Screw 9 Middle segment 10 Lower segment 11 Screw 12 Engagement profile 13 Component 14 Tooth cutting portion 15 Insertion aid 16 Tooth of component 17 Upper segment 18 Clamping teeth 19 Recess 20 Step of upper segment 21 Step of middle segment 22 Bolt 23 Tooth tip 24 Tooth root, tooth back surface 25 Tooth surface 26, 27, 28 Side surface 29 Tooth surface 30, 31, 32 Side surface 33-36 Step 37 Wing 38 Anti-rotation profile 39 First front surface of clamping teeth 40 Second front surface of clamping teeth 41 Chamfer 42 Tooth surface of tooth of component H ₂₇ - H ₃₂ height SpU Circumferential play SZ Tooth thickness of clamping teeth

Claims (14)

A clamping insert (5) for a clamping jaw of a clamping chuck, comprising:
a retaining segment (4) fixed to the clamping jaw (2) of multi-piece construction, on which individual clamping teeth (18) are retained, each of said clamping teeth (18) describing as a whole a toothed engagement profile (12) curved in accordance with the dimensions of the toothed component (13) to be clamped, said clamping teeth (18) being received in said retaining segment (4) with play in the circumferential direction,
1. A clamping insert (5) comprising: a retaining segment (4) comprising three overlapping and fixedly joined segment parts (9, 10, 17), namely a lower segment (10) adapted to be placed on the body (3) of the clamping jaw (2), an intermediate segment (9) placed on the lower segment (10) and an upper segment (17) covering the intermediate segment (9), wherein recesses (19) are formed in the intermediate segments (9) for receiving one clamping tooth (18) in each case, and wherein the upper segment (17) of the retaining segment (4) has a number of tooth-shaped insertion aids (15) which corresponds to the number of the clamping teeth (18) . A clamping insert (5) for a clamping jaw of a clamping chuck, comprising:
a retaining segment (4) fixed to the clamping jaw (2) of multi-piece construction, on which individual clamping teeth (18) are retained, each of said clamping teeth (18) describing as a whole a toothed engagement profile (12) curved in accordance with the dimensions of the toothed component (13) to be clamped, said clamping teeth (18) being received in said retaining segment (4) with play in the circumferential direction,
A clamping insert (5), characterized in that the three clamping teeth (18) are held in the retaining segment (4), and at least the two outer clamping teeth (18) have play in the circumferential direction. 3. The clamping insert (5) according to claim 2 , characterized in that each clamping tooth (18) is provided for engaging with a respective second tooth space of the component (13) to be clamped. A clamping insert (5) for a clamping jaw of a clamping chuck, comprising:
a retaining segment (4) fixed to the clamping jaw (2) of multi-piece construction, on which individual clamping teeth (18) are retained, each of said clamping teeth (18) describing as a whole a toothed engagement profile (12) curved in accordance with the dimensions of the toothed component (13) to be clamped, said clamping teeth (18) being received in said retaining segment (4) with play in the circumferential direction,
The clamping insert (5), characterized in that the clamping teeth (18) have stepped tooth flanks (25, 29). 5. The clamp insert (5) according to claim 4, characterized in that in a cross section of the clamp tooth (18) perpendicular to the axial direction, the stepped portion of the first tooth flank (25) and the stepped portion of the second tooth flank (29) are not mirror-symmetrical with respect to a line connecting the center of the tip (23) and the center of the root surface (24) of the clamp tooth ( 18 ). 6. The clamping insert (5) according to claim 5, characterized in that the tooth flanks (25, 29) each have three straight flanks (26, 27, 28; 30, 31, 32) therein, the two flanks (26, 30) connecting to the tooth tip (23) being of equal length and inclined so that the two planes in which the flanks (26, 30) lie intersect in front of the front face (39) of the clamping tooth ( 18 ). 7. The clamping insert (5) according to claim 6, characterized in that the intermediate flanks (27, 31) and the outer flanks (28, 32) bordering the tooth root (24) together extend more than half the tooth depth ( _H18 ) measured in the radial direction, and the ratio of the height ( _H28 , H32) of the outer flanks (28, ₃₂ ) to the height ( _H27 , H31) of the intermediate flanks (27, ₃₁ ) is between a minimum of 7:10 and a maximum of 13:10 for the first tooth flank (25) and between a minimum of 17:10 and a maximum of 23:10 for the second tooth flank (29). The clamping insert (5) according to any one of claims 4 to 7 , characterized in that the clamping tooth (18) has a tooth root (24) that is curved in an arc . A set of clamping inserts (5) for a clamping chuck (1), comprising:
9. A set of clamping inserts (5) according to claim 1, wherein a first subset formed of the clamping inserts (5) consists only of clamping teeth (18) having play in the circumferential direction of the clamping chuck (1), whereas a second subset formed of three clamping inserts (5) has only one clamping tooth (18) per clamping insert (5) which is held without play. 10. The set of clamping inserts (5) according to claim 9, characterized in that the set of clamping inserts (5) is formed from six clamping inserts (5) each having three clamping teeth (18), the respective central clamping teeth (18) of each clamping insert (5) incorporated in the second subset being held without play, whereas the remaining clamping teeth (18) on both sides of the same clamping insert (5) have play in the circumferential direction. 10. The set of clamping inserts (5) according to claim 9, characterized in that each clamping insert (5) of the second subset only has a single clamping tooth (18), which is fixed without play and against rotation to the holding segment (4) by means of a two -winged anti-rotation contour (38). A method for fastening an externally toothed component (13) with its teeth (14), comprising the steps of:
a plurality of clamping inserts (5), each having an engagement profile (12) curved in accordance with the dimensions of the toothed component (13) and formed by individual clamping teeth (18), are engaged with the teeth (14) of the component (13) to be clamped, and only three of the clamping teeth (18) of the entire set of the plurality of clamping inserts (5) are fixed without play in one clamping insert (5) so as to be distributed at intervals of 120° , while all the remaining clamping teeth (18) have play in the clamping insert (5) in the circumferential direction of the component (13). 13. The method according to claim 12 , characterized in that the component (13) is gripped by the clamping insert (5) on six peripheries totalling more than 210°. 14. Method according to claim 12 or 13 , characterized in that by means of the clamping insert (5) a connection body (13) of a transmission synchronizer is gripped.

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